Method of dyeing mixtures of animal fibers and synthetic polyamide fibers with reservation of the latter



United States Patent METHOD OF DYEING MIXTURES OF FIBERS AND SYNTHETIC POLYAMIDE FIBERS WITH RESERVATION OF THE LATTER Ludwig Thummel and Maurice Aeberhardt, Basel, Switzerland,'assignors, by mesnc assignments, to Saul & Co., Newark, N. J., as nominee of Fidelity UlllOIl Trust Company, executive trustee under Sandoz Trust 3 No Drawing. Application March 26, 1953 Serial No. 344,882

Claims priority, application Switzerland March 28, 1952 4 Claims. (Cl. 8-21) Synthetic polyamide fibers have heretofore been reserved against acid dyestufis, metallization dyestuffs and metal complex dyestuffs by treatment with sulfurized phenol derivatives. However,'a weakly alkaline bath is required in order to bring the sulfurized phenols into solution so that, while mixtures of cellulose and polyamide fibers can be treated with sulfurized phenols, the treatment of mixtures of animal and synthetic polyamide fibers encounters difliculties. Mixtures of animal and synthetic polyamide jfibers are, as is known, generally dyed in an acid bath. However, in the presence of acids, the sulfurized' phenols are precipitated and, as a result, lose most of their effectiveness. It is true that account can be taken of this disturbing property of the sulfurized phenols by carrying out the dyeing in a neutral to weakly alkaline bath and/or with the addition of wool protecting-agents or dispersing agents,which expe dientsand particularly the latterrender'the dyeing process cumbersome and expensive- Moreover, it is to be noted that when 'one of the last-mentioned processes is employed, the feel of the wool, even if wool protecting agents are added, becomes harder and rougher and does not satisfy modern requirements.

It is also old to add large quantities of sodium sulfate or} sodium chloride to the dyebath to strip acid dyestuffs from synthetic polyamide fibers or to retard the dyeing process on such fibers. However, the extent of these effects is relatively insignificant. For this reason, sodium sulfate and sodium chloride can not be regarded as actual reserving agents. It is true that, with quantities in excess of 50 grams of sodium chloride per liter of dyebath, it is possible, in the dyeing of mixtures of animal and synthetic polyamide fibers, to achieve a weak reserving action on the latter; however, the drawing of the dyestuif onto the animal fibers is commensurately retarded. There is thus a distinct need in the art for a process which would make it possible to obtain a satisfactory reserve on synthetic polyamide fibers in the single-bath acid dyeing thereof simultaneously with animal fibers. It is a primary object of the invention to embody such a process as well as. tolembody a dyebathwherein' the process may be carried out. i

The foregoing object is realized, according to the present invention, briefly stated, by carrying out thedyeing of the synthetic polyamide fibers with an acid d'yestuff, a metallizable dyestulf or a metal complex dyestufi, in the presence in the dyebath of a nitrate, bromide, iodide or thiocyanate ion, whereby a strong and specific reserving action on the said polyamide fibers is achieved. Thus, in the dyeing of polyamide-wool mixed fabrics in a dyebath which contains awater-soluble nitrate, bromide, iodide or thiocyanate of a metal with an atomic number from 3 to 56, such as for example of sodium, potassium,

magnesium, calcium, barium, zinc, tin, etc., as well as Patented Jan. 20, 1959 2 of ammonium, a striking reserving action-and even a white reserve-of the synthetic polyamide fibers is achieved. The hereinbefore-mentioned troublesome pre cipitation of the reserving agent in the dyebath is not encountered, nor is there any impairment of the feel and appearance of the animal fibers.

A reserving action which, in some cases is an enhanced action, can be realized, according to the present invention, by the presence in the dyebath of a mixture of the aforementioned water-soluble salts with each other or with a water-soluble chloride of a metal having an atomic number from 20 to 56.

The reserving of the synthetic polyamide fibers is realized, according to the present invention, with additions of from 5 to 20 grams of the salt or mixture of salts per liter of dyebath. In this manner, the desired reserving action is obtained, but without'concomitant retardation of the drawing of the dyestutf onto the animal fibers.

The addition of a dispersing agent to the dyebath is advantageous and results in an enhancement of the action of the added salt or mixture of salts so that, in a large number of cases when dyeing polyamide-wool mixed Illustrative of acid dyestuffs which are suitable for use in the preparation of the dyebaths according to this invention are inter alia the following, the Colour Index (C. 1.) numbers of which are taken from the 1st edition of the Colour Index, Bradford, 1924, or which are listed in the First Supplement of the Colour Index (S. C. I.): v,

Xylene Yellow S (C. I. No. 637), Xylene Light Yellow R '(C. I. No. 639), Xylene Light Yellow 3GS (C. I. No. 639), Xylene Light Yellow 26 (C. I. No. 639), Tartraphenine (C-. I. No. 640), Xylene Fast Orange G (C. I. No. 27), A20 Rhodine 2G (C. I. No. 31), A20 Rhodine 6B (C. I. No. 57), Brilliant Sulfon Red B (C. I. No. 32), Brilliant Sulfon Red SE (C. I. No. 32), Brilliant Sulfon Red 10B (C. I. No. 54), Ponceau R (C. I. No. 79), Carmoisine conc. (C. I. No. 179), Acid Bordeaux B (C. I. No. 88), Xylene Red B (C. I. No. 748), Xylene Violet RL (C. I. No. 53), Xylene Cyanole FF (C. I. No. 715), Xylene Blue VS (C. I. No. 712), Alizarine Light Blue B (C. I. No. 1054), Xylene Fast Green B (C. I. No. 735), Alizarine Light Green GS (C. I. No. 1078), A20 Rubinole 3G8 (S. C. 1., page 28), etc. Illustrative of metallizable dyestuffs which are suitable for use according to the present invention are the following, the designation S. F. having reference to the listing in the 7th edition of Schultz Farbstofftabellen, Supplement I, Leipzig 1934:

Alizarine Red SZ (C. I. No. 1034), Omega Chrome Brown 2R (C. I. No.98), Omega Chrome. Blue FB (C. I. No. 179), Omega Chrome Fast Blue B (C. I. No. 179), Omega Chrome Red G (S. C. 1., page 48), Omega Chrome Cyanine GR (S. F., page etc.

Illustrative of metal complex compounds which can be used, accordding to the present invention in the preparation of dyebathswhich reserve polyamide fibers, are the chromium compounds of azo dyestuffs which can be prepared according to German Patent No. 282,987 from diazotized 1-hydroxy-2-aminobenzenes, diazotized orthoamino-hydroxynaphthalenes or diazotized 2-aminobenzene-l-carboxylic acid or of derivatives of these submerit of azo dyestuffs which contain chrornable groups in the molecule according to German Patent No. 338,086; etc.

The following examples set forth representative illustrative embodiments of the invention, and are not at all intended to be limitative of the latter. In the examples, the parts and percentages are by weight; the temperatures are expressed in degrees Centigrade; and, as before, the C. I. (Colour Index) numbers have reference to the 1st edition of the Colour Index, Bradford 1924, while the S. C. 1. references are to the First Supplement of the Colour Index.

Example 1 100 parts of a fabric consisting, two-thirds, of wool fibers and, one-third, of synthetic polyamide fibers are entered at 40-50 into a dyebath consisting of Parts Tartraphenine (C. I. No. 640) 0.8

Concentrated sulfuric acid 2 Sodium nitrate 160 and 7 Water 8000 The dyebath is then heated slowly to 100, after which it is maintained at boiling temperature for 45 minutes. The mixed fabric is then rinsed and dried. The Wool fibers are dyed yellow, while the synthetic polyamide fibers are reserved.

Example 2 The procedure set forth in Example 1 is'followed except that the dyebath is replaced by a dyebath consisting of Parts Azo Rhodine 6B (C. I. No. 57) 1.6 Concentrated sulfuric acid 2 Potassium bromide 80 and Water 8000 There is thus obtained a mixed fabric, the wool fibers of which are dyed red, while the synthetic polyamide fibers are reserved.

100 parts of a mixed fabric, consisting one-half of wool fibers and one-half of synthetic polyamide fibers, are digested at boiling temperature, whereupon the wool fibers are dyed blue and the synthetic polyamide fibers are reserved.

Example 4 The procedure according to Example 3 is followed except that the dyebath is replaced by a dyebath consisting of Parts Xylene Fast Green B (C. I. No. 735) 1.3 Concentrated sulfuric acid 2 Ammonium thiocyanate 64 Dispersing agent: Oleyl polyglycol ether 16 and Water 8000 There is obtained a mixed fabric, the wool fibers of which are dyed green while the synthetic polyamide fibers are reserved. The oleyl polyglycol ether contains 20- 25 ethenox-y groups.

4 Example 5 100 parts of a mixed fabric, which consists /s of wool fibers and A; of synthetic polyamide fibers, is entered at 50 into a dyebath which consists of Parts The chromium complex compound of the monoazo dyestuif obtained by coupling diazotized l hydroxy 2 aminobenzene 4,6 disulfonic acid with 2,4-dihydroxyquinolin 2.75 Concentrated sulfuric acid 6 Ammonium thiocyanate and Water 8000 The temperature of the bath is slowly raised to 100, and the dyeing carried out for one hour at boiling temperature. Upon completion of the dyeing process, the mixed fabricthe wool fibers of which are dyed red, while the synthetic polyamide fibers are reserved-is withdrawn, rinsed and dried.

The same effect is obtained, if, in the foregoing, the 80 parts of ammonium thiocyanate are replaced by a mixture of 40 parts of ammonium thiocyanate and 40 parts of zinc bromide, or by a mixture of 48 parts of ammonium thiocyanate, 16 parts of zinc chloride and 16 parts of a dispersing agent.

An equally good reserving action is obtained upon replacement of the dyesufi recited in the first paragraph of the present example by the chromium complex compound of the monoazo dyestuff prepared from diazotized 1 hydroxy 2 amino 4 chorobenzene 6 sulfonic acid and 1-phenyl-3-methyl-5-pyrazolone 3-sulfonic acid.

Example 6 (a) 100 parts of a mixed fabric consisting of Va wool fibers and /a synthetic polyamide fibers are subjected to a dyeing operation in a dyebath consisting of Parts Omega Chrome Red G (S. C. 1., page 48) 1.5

Acetic acid 2 Ammonium thiocyanate 80 and Water 8000 by entering the fabric into the bath at 50, slowly raising the temperature of the bath to 100, and then maintaining the bath at the latter temperature for a half hour. 2 parts of formic acid are then added to the dyebath, which is then boiled for an additional half hour. The dyed materialthe wool fibers of which are dyed, but the synthetic polyamide fibers of which remain reserved.- is then boiled in the same bath (after the addition of 0.75 part of potassium bichromate) for one hour, after which the material is rinsed and dried.

(b) The procedure in part (a) of the present example is repeated, except that the 80 parts of ammonium thiocyanate are replaced by a mixture of 40 parts of ammonium thiocyanate and 40 parts of zinc iodide or by a mixture of 64 parts of ammonium thiocyanate and 16 parts of dispersing agent or by 80 parts of potassium bromide. In each case, an essentially similar result is obtained, the wool fibers being dyed and the synthetic polyamide fibers being reserved.

Example 7 A mixture consisting of a natural silk fabric (50 parts) and a fabric of synthetic polyamide fibers (50 parts) is entered at 4050 into a dyebath consisting of Parts Brilliant Sulfon Red SE (C. I. No. 32) 0.9 Formic acid (85%) 2 Ammonium thiocyanate 48 Zinc chloride 16 Dispersing agent: Dodecylphenyl polyglycol ether. 16 and Water The dodecylphenyl polyglycol ether may be replaced by any other suitable alkylphenyl polyglycol ether or by an alkyl polyglycol ether such as cetyl or stearyl polyglycol ether. The dyebath is gradually heated to 100 and then maintained at this temperature for 45 minutes. The two fabrics are then washed and dried; the natural silk is dyed red, while the polyamide fiber fabric remains undyed.

The same result is obtained if, in the foregoing, only 8 parts of dispersing agent are employed.

Instead of two fabrics, use may be made-with the same result-of a single fabric comprising equal parts of natural silk and synthetic polyamide fibers.

Example 8 (a) 10 parts of a synthetic polyamide fiber skein are boiled for 45 minutes in a dyebath consisting of The skein is then rinsed; it is only imperceptibly soiled, substantially all the dyestutf remaining in the dyebath.

(b) The procedure according to part (a) of the present example is repeated with a dyebath consisting of Parts Alizarine Light Blue B (C. I. No. 1054) 0.1

Concentrated sulfuric acid 0.2

and

Water ,800

The thus-treated skein is dyed a beautiful blue, and the dyebath is substantially completely exhausted.

Upon completion of the dyeing according to the present invention, as exemplified for instance in the preceding examples, the exhausted dyebath, containing the added salt or mixture of salts or mixture of salt or salts. and dispersing agent, may be re-employed for further dyeing operations, subject of course to the addition of the requisite quantity of dyestuff. Such re-used baths exhibit the aforedescribed reserving action of the original baths.

If desired, the treatment according to the present invention, as exemplified for instance by Examples 1 to 8, may be supplemented by an over dyeing treatment for the reserved polyamide fibers, this treatment being carried out in a fresh dyebath which does not contain any salt or mixture of salts or mixture of these with dispersing agent. In such a bath, the reserved fibers are forthwith dyed. Mixed color effects can thus be achieved.

Metals having an atomic number of 3 to 56 in the sense of the foregoing are for example Li, Na, K, Mg, Ca, Sr, Ba, Zn and Sn. The particular nitrate, bromide, thiocyanate or iodide, used by way of illustration in any of the foregoing examples, may be replaced by an equivalent amount of a corresponding salt of any of the iust- 6 enumerated metals, essentially the same result-dyeing of the animal fibers and reserving of the polyamide fibersbeing in each case obtained.

The synthetic polyamide fibers mentioned in the introductory portion of the present specification and in the several examples refer to the fibers of the type known as nylon (cf. U. S. Patents Nos. 2,071,250-3; 2,130,947-8; 2,149,273; and others), Perlon, Grilon, etc., and any one of these may be used where the examples call for synthetic polyamide fibers.

Instead of the dispersing agents mentioned in the foregoing examples, use may be made of, for example, any one of the following: alkyl aryl sulfonates (alkyl benzene sulfonates and alkyl naphthalene sulfonates), highly sulfonated oils, Turkey red oil, fatty acid condensation products, higher molecular alkyl sulfates; and many others. Having thus disclosed the invention, what is claimed 1. A method for dyeing a mixture of animal fibers and synthetic polyamide fibers with reservation of the latter, which comprises dyeing the mixture of animal fibers and sythetic polyamide fibers in an acidic aqueous dyebath containing an acid dyestuff in the presence, in the dyebath, of at least 5 grams to at most 20 grams of salt per liter of dyebath, the said salt yielding anions selected from the group consisting of nitrate, bromine, iodine and thiocyanate anions and cations selected from the group consisting of ammonium, sodium, potassium and zinc cations, water being the sole elfective solvent in the dyebath.

2. A method according to claim 1, wherein the dyeing is carried out in the further presence, in the dyebath, of a dispersing agent, the total quantity of salt plus dispersing agent being at least more than 5 to at most 20 grams per liter of dyebath, there being at least 5 grams of salt per liter of dyebath.

3. A method according to claim 1, wherein the dyeing is carried out in the further presence, in the dyebath, of chlorine anions and zinc cations, the total quantity of salt being at least 5 to at most 20 grams per liter of dyebath.

4. A method according to claim 3, wherein the dyeing is carried out in the further presence, in the dyebath, of a dispersing agent, the total quantity of salt plus dispersing agent being at least more than 5 to at most 20 grams per liter of dyebath, there being at least 5 grams of salt per liter of dyebath.

References Cited in the file of this patent UNITED STATES PATENTS Rittinghausen May 12, 1936 Olpin Oct. 28, 1952 OTHER REFERENCES 

1. A METHOD FOR DYEING A MIXTURE OF ANIMAL FIBERS 